Scars of the Past
by Raisin Cookies
Summary: Erin's half sister arrives in Chicago after running from her abusive boyfriend. Terrified of trusting anyone she quickly realises that not all cops are the same when she needs to turn to Jay and the team for help. Jay/OC


Chapter One

The trembling in Katie's hands never seemed to stop; nether didn't the nauseating churn within her stomach. She jumped at every loud noise and eyed everyone with wariness and trepidation. Even the distance that she had put between herself and Miami didn't seem to offer her any comfort. The greyhound bus shuddered to a stop, the grunting and groaning of the engine giving a final splutter, as the driver killed the motor at Dan Ryan bus terminal. She was here; she had made it.

As she made her way off of the bus the driver had already started to unload the suitcases from the hold, he caught her eye and squinted, immediately catching sight of the purplish bruise which covered her cheekbone and jaw. The colour had deepened considerably since she boarded the bus eight hours ago in Williamsburg and now not ever her oversized sunglasses could cover the worst of it.

"Thank you," she whispered as she collected her two suitcases. Her voice was gravely from lack of use; he gave her a sympathetic smile and shot a friendly wink before continuing to unload the rest of the luggage.

"Katie!" she turned around at the sound of her name and quickly spotted Erin walking towards her in a thick puffy parka and flat black boots. She stumbled towards her, forgetting momentarily about the suitcases at her feet and threw her arms around her half sister.

Erin squeezed back tightly, "thank God you're here," she murmured into her ear.

She couldn't stop the tears from flowing; it was as though the dam of emotions she had kept at bay for the last few days had finally crumbled. She was finally safe. Erin would protect her now and Danny would never hurt her again.

\- - - - - -  
"Damn son of a bitch. He did this to you?"Erin demanded angrily as she stood in Erin's apartment showing her the damage of what he'd done. She had a horizontal cut on her waist which was fairly deep into her skin. She had bandaged it up with gauze from the drug store which seemed to have temporarily stemmed the bleeding but it hurt badly and stung horribly if she twisted the wrong way.

"You need stitches," she exclaimed and covered her mouth to take a moment. Sometimes her anger got the better of her and she knew that that was the last thing that Katie needed right now; another angry person to deal with.

She drew a deep breath, "I'm sorry."

Katie's lip trembled, "it's going to leave a scar, isn't it?"

She placed her hands on her younger sisters shoulders and tried to be calm as she looked over the cuts and bruises on her chest and face, and the scratches and scrapes which marked her arms and thighs.

"I've got you now. I'm going to protect you and keep you safe and Danny will never lay another finger on you for as long as he lives or, help me God, I will shoot him. Do you understand me?"

Katie nodded and sniffed noisily as she blinked back a fresh onslaught of tears.

"I need to call someone; he's friend and doctor."

When Katie didn't argue she gave her a quick nod and pulled out her cell phone; holding her sister's gaze as it rang.

"Hey, Erin, did you phone the wrong Halstead?" the voice on the other end quipped.

Erin was in no mood for banter, "Will, I have a problem. I need help but I need things to stay quiet".

Will's voice turned serious, "how bad?"

"I need someone who can do stitches and not ask for medical records".

"I'll be at your apartment in twenty minutes," he stated before quickly disconnecting the call."

She looked back at Katie who was currently pursing her lips together tightly; she looked so small and fragile at this moment in time. She had lost weight since the last time she had seen her and Erin wondered why it taken Katie so long to ask for help; but she didn't want to get into, at least for now.

"Will, Jay's brother, he's a doctor and he's on his way over," she paused and flipped the phone over a few times in her hand, "you could press charges."

Katie shook her head furiously, "no police, Erin. Please?"

Erin held up her hands in surrender, "okay, no police. I'll try my best to keep Hank at bay but he's going to figure that something is up. We'll work it out though. I promise."

Will swallowed hard the moment he caught sight of Katie as he made his way into Erin's apartment. He had been here plenty times before but not since she and Jay split. It had been a mutual decision; they loved each other, but they weren't in love with each other. Despite having known Erin for about three years he'd never actually met her sister, or half sister to be more accurate. He immediately saw the resemblance; whilst Katie was more petite than her older sister and her hair was darker, they shared the same nose and had matching dimples. He saw the scratches on Katie's neck which peeked out from the top of the cosy flannel shirt she was wearing. It was at least one size too big for her. He saw the angry purple bruising which had formed over her face and quickly shelved his anger and replaced it with his 'Dr-Halstead-I-will-remain-professionally-detached' persona.

Erin ushered him through the apartment, "Will, this is my sister Katie."

Katie blinked at him and flicked her eyes back to her sister, seeking comfort.

Will smiled at her patiently and set his medical bag on the arm of the sofa, "It's nice to finally meet you, Katie. Why don't you have a seat and show me this cut that Erin thinks might need stitches."

She made no effort to move, after a few moments Erin stepped over to her sister and gently guided her around so that her back was to Will then gently lifted the hem of her shirt to reveal the bloodied bandages which covered her right side.

Will let out a deep sigh and looked around the room wondering what the best way to do this was. "Okay, why don't you lay down on your side on the couch." He gently guided her down, "and lean a little towards me. Okay perfect."

He worked tenderly to remove the bandages as Erin brush the hair from her sister's face soothingly. Erin had been right; the wound was deep into her side but hadn't really caused any serious damage.

"Who did this to you, sweetheart?" he asked softly.

"My boyfriend," she whispered.

"Ex-boyfriend," Erin corrected quickly.

"Are you hurt anywhere else, somewhere that I can't see?" he asked

They both knew what he meant.

Katie shook her head, "I got away from them before..." she trailed off as her voice cracked.

Erin and Will shared a look which told him that not even she knew that part of the story.

Erin wasn't shocked when Jay showed up, and neither was Will judging from the slightly guilty expression on his face. They had just been finishing up with Will checking the bruising along Katie's cheekbone. He'd wanted to make sure that it wasn't fractured.

He had let himself in with the spare key which he had never given back after he moved out. His face was stubbly and unshaven and he was dressed in his customary dark jeans and charcoal grey Henley.

She knew Katie was embarrassed about everyone crowding the apartment in seeing her in her battered state. She got to her feet and moved to stand between him and Katie, "Will called you?" she asked, although she already knew the answer.

Jay shrugged, "of course he called me. He got a phone call from you asking for help." He paused, "are you going to introduce me to your sister?" he asked as he gestured behind Erin. The protective stance that Erin had taken did not go unnoticed.

Erin rubbed her forehead with the heel of her hand; this was turning out to be a really long day.

"Jay, this is Katie. Katie, Jay."

Jay smiled kindly at the young woman, "it's good to meet you, Katie. I'm sorry it's like this, though." He said genuinely. He looked her over, his eyes drawn to the massive bruise on her face and the pile of bloody bandages and medical supplies which were strewn over the coffee table where Will sat.

He turned back to Erin, "tell me what I can do to help."

She offered him a tired grateful smile, "I don't think that there's anything you can do right now. Katie's exhausted. I'm exhausted. Perhaps, just keep this quiet, at least for the time-being."

He nodded reluctantly, "you've got it."

Erin saw them both to the door and thanked Will again for his help.

"Do you think they'll tell anyone?" Katie asked her quietly once it was just the two of them again. What she really meant was, what if they tell Hank. "What if someone contacts Miami PD? Danny will figure out where I am."

"Don't worry about that. I told you that I would take care of everything, and I will."

Jay twisted the cap off a bottle of beer and flung the cap on the counter. It bounced a few times, the clanking breaking the silence which filled his and Will's apartment. "How many stitches did she get?"

"Seventeen. It looked like a knife wound. You should've seen her, Jay. She is covered in cuts and bruises; that guy really did a number on her."

"What about sexual assault?"

"She said no, and I wasn't going to press the issue."

Jay nodded and took a swig from his bottle. He couldn't help but think of Erin's sister Katie and how sad her eyes were. Both he and Erin knew that they weren't right for each other, they tried hard to make it work but in the end the end the love just wasn't there, but that didn't mean that he didn't care. Voight articulated it much better than Jay ever could; an attack on your family is an attack on our family.

It was a few days later and Erin had successfully managed to dodge Voight; she was reluctant to let him know that Katie was in Chicago. He would want to see her and then they'd have to explain the bruises and that in itself would open a whole can of worms that neither she nor Katie wanted to have to deal with right now. Her main priority was getting Katie healed and feeling safe again.

She was standing at the counter making toast for breakfast and Will was due to stop by soon to check on the stitches./p  
p class="MsoNormal""He said that it wouldn't take him long; he just needs to make sure that everything is healing okay and there's no infection."

"There isn't. I checked in the mirror and they look fine," she protested. "Can't you call him back and tell him not to bother?"

Erin rolled her eyes, "Listen, both Will and Jay have asked loads of times in the last few days how you're doing. Neither one of them is going to be fobbed off with a phone call. Just let him do his doctor thing and then he'll leave."

She sat the plate of buttery toast down in front of Katie and gave her a pleading look before starting to munch on a slice.

Katie pulled a triangle from the plate and picked half-heartedly at the sunflower seeds scattering the crust, "I thought he loved me," she told her sister quietly. She was humiliated that she had fallen for his charm and shallow one liners. Desperately hunting and clinging to love regardless of how destructive it was; maybe it had been to replace the love that she never received from either of her parents.

"In a weird way he probably did." Erin told her.

Erin had gone back to work which now left Katie at a loose end during the day. Erin had tried to convince her to go out and see the sights of Chicago; she had only been little when her Aunt, on her father's side, had taken her to live in Miami. At that time her family had been scattered, her father was in prison on an assault charge and her mother, Bunny was a drug addict and alcoholic. Her half siblings, Erin and Teddy were pretty much left to fend for themselves.

For the time-being she was content to stay indoors, at least until her bruises had healed and she at least had a warm coat. Winter in Chicago was rough and needless to say, nothing like the non-existent Miami winter. Even now as she curled up on the sofa reading a book the snow was falling outside in massive clumps; she was fairly certain that her converse and sandals would do little to stop her face planting against the pavement.

She jumped a little at the soft rapping knock against the front door. A little startled she quietly untangled herself from the soft fleecy blanket which she had pulled over her lap and tip toed to the door. Through the peephole she spotted a familiar face; Erin must have sent him she thought as she nervously unlocked the door and released the security chain. She pulled the door open a few inches and looked up into the ruggedly handsome face of Jay Halstead.

He smiled brightly at her, "hey" he greeted.

She looked at him questioningly, "hi" she responded, not quite sure what to say to him.

"Um, Erin asked if I could stop by, she's been held up on a case so I thought I bring supplies,"

It was then that she noticed he was carrying a red box with Do-Rite Donuts and a carrier with two coffee containers.

"Can I come in?" he asked.

She scratched her head and looked back into the wider open space of Erin's apartment, "Um," she delayed answering hoping that an excuse might come to her, and come to her quickly. It didn't.

Jay's voice softened. "Hey, Katie, I'm not here to scare you. I just...I told Er that I would stop by and make sure that you were doing okay. She's being worrying."

She automatically felt guilty, she didn't want Erin to be worrying about her all day, not when she had already done so much for her. Despite being sisters they actually barely knew one another; Katie had travelled up to Chicago a few times to meet her and Bunny and Erin pseudo stepdad, Hank. They hadn't really spoken in years, not since they were kids and it was only recently that they had found each other again through Facebook.

Slowly she pulled the door open and stepped back to indicate that it was okay for him to come in. He settled in the armchair as Katie sank back into the comfort of the couch. She inhaled the heady aroma of coffee from the container that Jay had passed her and her mouth tugged up in a small smile. "It smells like caramel."

Jay grinned. "Wait until you try the donuts, they're seriously addictive."

He watched her as she took a long swig from the cup. Her loose pink sweater hung to one side and exposed her bare shoulder smattered with bruises and grazes. She caught his gaze and embarrassed she readjusted her top.

His voice was gravely but he spoke softly, "if you tell me who is was I'll make sure they never hurt you again, Katie."

She shook her head and pick at the label on her cup, "it doesn't matter now. I'm here and I'm never going back."

He nodded accepting, at least temporarily, that she wasn't going to open up just yet. He switched back to the lighter topic of conversation and grabbed the box of donuts from the table.

"Now these, are my absolute favourites. If you don't like these then we're going to have a serious problem." He told her as he pulled out two. "Valrhona Chocolate Cake or Michigan Apple Fitter?"  
She smiled softly and pointed at the one she wanted, "chocolate, please."

Jay let out a chuckle, "chocolate. How did I know you would choose that one?"

She gave a smile and little shrug as her teeth bit through the rich chocolate ganache.

They ate in silence, watching the snow continue to fall from inside the warmth of Erin's apartment. When they were done eating they drank their coffees and made small talk. She started to relax a little in his presence. The subtle scent of him was almost comforting; the smell of his leather jacket and spices of his cologne mixed with the sweet smell of the pastries and coffee from the bakery. She would never share this; he was Erin ex and she would never betray her like that but at the same time couldn't deny the yearning feeling of happiness that was starting to tug at her as they talked.

Erin grunted in pain as she slowly made her way from the bedroom to the kitchen. The day before she had been tackled awkwardly by a suspect; despite taking the longest, hottest shower in history she still woke up this morning feeling like she'd been hit by a bus.

Katie was in the kitchen pouring two large mugs of coffee from the pot.

"In a lot of pain?" she asked.

Erin nodded and grabbed a tube of Deep Heat she had wisely purchased last night on her way home from work. A loud knock came from the door.

"I'll get it," Katie called as made her way quickly there and threw the door open widely before checking the peephole.

"Katie!" a horse voice exclaimed in surprise. "What are you doing here, kid?"

Katie looked up at the older man, and watched as his eyes narrowed and his jaw jutted out angrily as he took in the fading purplish and yellow bruises which were slowly but surely getting better.  
Erin rounded the corner to see who was at the door and stopped dead in her tracks at the sight of Voight.

"He raised a finger and pointed accusingly between the two of them.

"I think that you ladies might need to bring me up to speed with exactly what is going on around here.

\- - - - - - -  
Thanks for making it to the end of chapter one!  
RC


End file.
